Fluid-pressure hoist.



No. 657,332. Patented Sept. 4, 1900.

N. A. CHRISTENSEN.

FLUID PRESSURE HOIST. (Application filed Aug. 21,1399. Rgnewed June 25, 1900.)

(No Model.) 2 Sheets-Shea! l.

345760060: five/72 0):

ms Nonms PETERS 0a.. moroufund WASHINGTON. n. c.

No. 657,332 Patented Sept. 4, I900.

N. A. CHRISTENSEN. v t FLUID PRESSURE HDIST.

(Application filed Aug. 21, 1899. Renewed June 25, 1900.)

(No Model.)

2 Shuts-Sheet 2.

UNITED STATES-PATENT OFFICE.

NIELSLANTON CHRISTENSEN, oF MILWAUKEE, wisooNsIN.

FLUID-PRESSURE HOIST.

SPECIFICATION forming part of Letters Ifatent N 0. 657,332, dated September 4, 1900. Application filed August 21, 1899. Renewed June 25, 1900. Serial No. 21,502. (No model.)

1'0 all whom it may concern: Y

Be it-known that I, N IELS ANTON GHRIs'rEN- SEN, a resident of Milwaukee, inthecounty of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Fluid-Pressure Hoists and the Like,of which the following is a specification.

My invention relates to fluid-pressure hoists and the like; and one of its objects is to provide novel, simple, and eflicient mechanism for controlling the pressure to and from the cylinder.

Another feature of my invention consists in an air-cushion formed at one end of the cylinder to prevent violent contact between the top cover and the piston on its full upward or inward stroke and also in a safety device in combination with other parts and comprising a check or nonreturn valve in the main air-pipe to prevent backflow of pressure through the reservoir-pipe, and thereby pre Vent dropping of the load in case such pipe should burst or part while the controlling valve is in application position and not in lap.

In the drawings, Figure 1 is an elevation of my hoist and controlling-valve Fig. 2, a sectional elevation thereof. Figs. 3, 4, 5, and 6 are details of the controlling-valvathe section shown in Fig. 3, except as to the valve 18, being taken on the angular line-3 3 of FigL i and the section of suchvalve 18 being taken" on line 3 of Fig. 6;.and Fig. 7, an enlarged detail view of the spring 25.

The cylinder 1 has the usual top coveror cap 2, a bottom cover or cap 3, a piston 4, and stuffing-box 5. The cylinder is provided with one or more ports 6 near its top end, and thepiston is of sufficient length so that upon full travel it will close said port or ports, and thereby an air-cushion will be formed at the top of the cylinder to prevent violent contact between the piston and the cover.

Compressed air is supplied from a reservoir or other suitable source to the main air-pipe 7, which is provided with a check or non-return valve 8, located in the air-pipe, preferably near the controlling-valve. This checkvalve permits free flow of air toward the controlling-valve, but prevents its return, whereby the pressure already admitted to the cylinder is maintained therein even though the controlling-valve may be in application posi- 'cess l or socket 17.

tion. The mainair-pipe communicates with -a port or passage 9 in the cover 3, which is also providedwith a cylinder port or passage 10, passing therethrough and entering the cylinder below the piston. The function of the controlling-valve is to govern the admission and release of pressure into and from the cylinder through the cylinder-port 10.

The controlling-valve consists, in general terms, of a base or valve-seat 11 and a bonnet or casing 12, within which operates a disk valve. This seat is secured to the cover 3 by bolts or otherwise, and the same has three ports or passages 13, 14, and l5,'all terminating 011 the face 16 of the valve-seat. The ports 13 and 14 communicate, respectively, with the ports 9 and 10, the port 13 being the reservoir-port and the port 14 the cylinderport, while the port 15 is the exhaust-port leading through the seat to the atmosphere. The seat is also provided with a central re- The inner wall of the valve-chamber may have a score or channel 12*, communicating with a passage or recess 13*, cut on the valve-seat and extending from the port 13. The purpose of such score is to drain away any water or moisture that may form or collect in the chamber or betweenthe very narrow clearance between thevalve and thewalls of the chamber. Ports l3, lat, and

115jare governed by the disk valve 18, operating'in the casing 12 and having an operatings'tem 19. The face of this valve is provided with means'for connecting any two of the ports, which means may consist, as shown, of two ports 20 and 21, connected by an internal passage 22, or, as is obvious, a single recess may serve the purpose. The valve has a central stem 18, received by the socket 17.

Upon one side of the casing or bonnet are arranged similar lugs 23, having holes to receive a pin 24, forming a pivot for a spring 25, whose intermediate portion is coiled around the pin and Whoseextreme free ends are formed substantially straight and extend around the casing on either side, so as to lie on either side of a projection orl-ug 26on the casing, which is located substantially diamet rically across from the lugs 23. The portions of the ends of the springs between the extreme ends and the coiled portion are curved to correspond with theeurvature of the casing.

too

I l he valv-stem 19' maybe operated bythe usual hand chains orropes, and totliis' endavalve-lVef device is secured to this 7 Stem,

ments of'thejlevers'in the two directions.

V a The normal or lap position ofthe disk vaive ismaintained by thespring-wnosefree ends. V keep the horn-30vdirectly beyond and in'line 1 with the projection 26. At this time all-the ports are closed and-the valve is said tobe on, lap. By th'e means shown I secure aposition 1 of lap which is absolutely definite, and the valve 'cannot'be changed fromthis position except by deliberate intent of the operator.

When one of thehand chains or ropes at,

tached to the arms 28 and29 is pulled torotale the valve to application posi-tion, the

portsin the face of thevalve connect the reservoir-port'witli the cylinder-port and corn pressedair is thereupon admitted to the cylf i'nder to operate the piston in the usualmaniner. The speed of admission'maybe' easii y regulated by the fullness of application due 7 to the amount of rotation of the valve whose full movement is limitedby contact of one of the hook-shaped arms against the pivot-pin. As the main air-pipe has a check-valve the compressed air can be kept in the cylinder] to hold theloadin case of accident to such pipe 'even while the disk valve is in application position, as just described. The diskv'a lve will be restored to lap position by thespring so soon as the operator releases the lever and the 'compressed air will be confined in the cylinder. or rope is pulled to rotate the valve in the opposite direction, whereupon the cylinderport will be connectedto the exhaust-port and the cylinder thereby exhausted. The

speed or amount ofv release of the cylinder: may thus be easily regulated and thespring will return the valve to a positive lap position immediately upon a. release of the hand chain or rope by the operator.

By the use of my invention I provideavallve which is not liable to leak, but is capableof performing its functions in a reliable and efficient manner, and in addition I. also provide means whereby a positive and definite vlap of-the valve is always assured.

While I have shown and described. my irrvention asapplied to a verticalhois-t,-. it will be understood that the same may be applied to cylinders and hoists of other types,and consequently I contemplate using my invention wherever applicable.

Although I have described more or less precise forms and details of construction, I do not intend to be understood as limiting-my self thereto,as I contemplate changes in form,

To release the air, the other chain.

fineness and-a single spring exerting its tension upon the vaive tdiidimally keep it in" lap position 1 and; tore-store it" tofsu'ch position after move- .lnentin one direction toa-pplieation position ".o'nafter inofenient in the oppositedirection' toreiease position. f p Y v I 2.-A fluid-pressure hoist comprising a fluid- .pressure-actuated piston traveling in a-cylinder, a casing having a} valve governing the admission and release of pressure to and from the cylinder and tension mechanism mounted on and extraneous of thec'asing and cooperatin'g. directlyl'with such valve to normally keep it in lap position and restore it to that position after movement to a position on either side of-lap'pos'i tion. T a v 3. A fluid pressure hoistco'm prising a fluidactuated pistontra-veling in a cylinder,=a valve governing the admission, and release of pressure to and-fromthe cylinder, a stem for such valve, and a spring having-its two free ends eoo-peratingdirectly with such stem and tending to resist movement thereof away from lap position. v

.4- A fluidpressure hoist comprising a cylinder having a piston and provided with inlet-,sexhaust and supply ports, a valve governing said ports by connecting the inlet'and -supply ports in application position and the inlet and 'exhaustfports' in release" position, an operating stein for the valve provided with an armor hornand a spring. directly engaging such horn and'exerting its tension against rotation of the stem.

5. A fluid-pressure hoist comprising acylinder having a piston and provided with inlet and exhaust ports,- afiuid-pressure-supplyport, avalve governing said ports, an operating mechanism for such valve, a casing for said valve, and a spring mounted on and extraneous of theca's-ing and bearing against said operating mecha-nismfor normallyina-intaining'the valve in lap position. and adapted -to automatically restore the same after move- 1 menttoapplication position or exhaust pov sition.

6. A fluid-pressure hoist comprising a cylinder having'a piston and provided with inlet and exhaust ports and also a supply-port, a valvego-verning said ports-,=a casin g. for said valve, operating mechanism for such valve, anda spring. pivoted on the casing! and having its ends-bearing againstsuch operating mechanism to keepthe valve in lap' position and-restorethe sameafte'r any movement out of such normal position.- I

7. A- fl-uid-pressurehoist comprising a cylinder having a piston and provided with inlet and exhaust ports and also a supply-port,

, the proportion of parts, and the substitution 7 release of pressure to and fromfthe cylinder.

in g and having its free ends bearin g on either side of such horn to maintain the valve in nor mal position.

8. A fluid-pressure hoist comprising a cylinder having a piston and provided with inlet and exhaust ports and also a supply or reservoir port, a valve governing said ports and having an operating-stem, a casing therefor having a lug or projection on one side, a pin mounted on the outside of the casing opposite the lug, a spiral spring pivoted to such pin and having its free ends extending on either side of the casing and on either side of such lug, lever-arms secured to the valvestem and ahorn movable. with said lever-arms and extending between the ends of such spring.

9. A fluid-pressure hoist comprising a cylinder having a piston and provided with in let and exhaust ports and also a supply or resvoir port, a valve governing said ports and having an operating-stein, a casing therefor, a coiled spring pivoted on one side of the casing and having its free ends extending substantially parallel across the casing on either side thereof, a hub connected to said valvestem and having diverging lever-arms and also having a horn extending to between the free ends of the spring whereby the movement of the valve in either direction is against the tension of the spring. v

10. A fluid-pressure hoist comprising a cylinder having a piston and provided with inlet and exhaust ports and also a supply-port, a valve governing said ports and having an operating-stem, a casing therefor, a hub secured to the stein and having actuating leverarms, means for normally holding the valve in lap position and a pair of projecting arms on the hub adapted to contact the casing respectively in full-release and full-application position.

11. A fluid-pressure hoist comprising a cylinder having a piston and provided with inlet and exhaust ports and also a supply-port, a casing connected to the cylinder and having a chamber and a rotary valve therein for governingsaid ports, said chamber having a score on its inner wall communicating with one of said ports to drain away moisture.

12. A fluid-pressure hoist comprising a cylinder having a piston and provided with inlet and exhaust ports and also a supply-port, a valve device governing said ports and having an operating-stem, a casing therefor, a pin mounted on the outside of the casing, a spring coiled around the pin and having its free ends extending across the casing on either side, lever-arms secured to the stem, a horn also secured to the stem, movable therewith and extending between the ends of the spring and a pair of projecting arms also secured to the stem and contacting, and limited in motion by, the pin in the full-application and full-release position of the valve, such pin forming a combined pivot-pin and a stop. 13. A fluid-pressure hoist comprising a cylinder having a piston and provided with a cylinder port or passage 10 and a reservoir port or passage 9, a base or valve-seat 11 secured to the cylinder and having ports 13 and 14 communicating with ports 9 and 10 respectively and an exhaust-port 15, a disk valve 12 having on its inner face port connecting means and working on such seat to govern the ports, a stem for the valve, a casing 12 for such valve having lugs 23, a pin 24 arranged therebetween, a spring having an intermediate spiral portion coiled around the pin and having its ends curved around on either side of the casing and then having its extreme free ends extending parallel, a hub secured to the valve-stem and having leverarms 28 and 29, and a projecting arm or horn 30 extending between the free ends of the spring intermediate of the lever-arms.

NIELS ANTON CHRISTENSEN.

Witnesses:

J. DADMUN, SAMUEL E. HIBBEN. 

